Merge pull request #1297 from PSeitz/fix_clippy

fix clippy issues

src/aggregation/bucket/range.rs

@@ -240,17 +240,15 @@ impl SegmentRangeCollector {
 /// more computational expensive when many documents are hit.
 fn to_u64_range(range: &RangeAggregationRange, field_type: &Type) -> crate::Result<Range<u64>> {
     let start = if let Some(from) = range.from {
-        f64_to_fastfield_u64(from, field_type).ok_or::<TantivyError>(
-            TantivyError::InvalidArgument("invalid field type".to_string()),
-        )?
+        f64_to_fastfield_u64(from, field_type)
+            .ok_or_else(|| TantivyError::InvalidArgument("invalid field type".to_string()))?
     } else {
         u64::MIN
     };
 
     let end = if let Some(to) = range.to {
-        f64_to_fastfield_u64(to, field_type).ok_or::<TantivyError>(
-            TantivyError::InvalidArgument("invalid field type".to_string()),
-        )?
+        f64_to_fastfield_u64(to, field_type)
+            .ok_or_else(|| TantivyError::InvalidArgument("invalid field type".to_string()))?
     } else {
         u64::MAX
     };

src/aggregation/collector.rs

@@ -124,7 +124,7 @@ impl AggregationSegmentCollector {
         agg: &Aggregations,
         reader: &SegmentReader,
     ) -> crate::Result<Self> {
-        let aggs_with_accessor = get_aggs_with_accessor_and_validate(&agg, reader)?;
+        let aggs_with_accessor = get_aggs_with_accessor_and_validate(agg, reader)?;
         let result =
             SegmentAggregationResultsCollector::from_req_and_validate(&aggs_with_accessor)?;
         Ok(AggregationSegmentCollector {

src/aggregation/metric/stats.rs

@@ -87,11 +87,8 @@ impl IntermediateStats {
     }
 
     pub(crate) fn standard_deviation(&self) -> Option<f64> {
-        if let Some(average) = self.avg() {
-            Some((self.square_mean() - average * average).sqrt())
-        } else {
-            None
-        }
+        self.avg()
+            .map(|average| (self.square_mean() - average * average).sqrt())
     }
 
     /// Merge data from other stats into this instance.

src/aggregation/mod.rs

@@ -918,8 +918,8 @@ mod tests {
             let collector = AggregationCollector::from_aggs(agg_req_1);
 
             let searcher = reader.searcher();
-            let agg_res = searcher.search(&AllQuery, &collector).unwrap_err();
-            agg_res
+
+            searcher.search(&AllQuery, &collector).unwrap_err()
         };
 
         let agg_res = avg_on_field("text");